If it is the Pro comp Block they are pretty good blocks but it takes a lot of machine work .
We did two of them last summer for some local guy's one of them we had to do a lot of honing on the cam journals to get bearing to fit it and then three of the cylinders were off center .
Both guy's ran them all season with no problems but you could be out a lot of money on the machine work .
Like Zip said just buy the SHP block still may require some machine work but not nowhere as much as the pro comp blocks .